Enhanced Near-cloak by FSH Lining

Hongyu Liu; Hongpeng Sun

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arXiv · 1110.0752

Enhanced Near-cloak by FSH Lining

Hongyu Liu·Hongpeng Sun

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Abstract

We consider regularized approximate cloaking for the Helmholtz equation. Various cloaking schemes have been recently proposed and extensively investigated. The existing cloaking schemes in literature are (optimally) within $|\ln\rho|^{-1}$ in 2D and $\rho$ in 3D of the perfect cloaking, where $\rho$ denotes the regularization parameter. In this work, we develop a cloaking scheme with a well-designed lossy layer right outside the cloaked region that can produce significantly enhanced near-cloaking performance. In fact, it is proved that the proposed cloaking scheme could (optimally) achieve $\rho^N$ in $\mathbb{R}^N$, $N\geq 2$, within the perfect cloaking. It is also shown that the limit of the proposed lossy layer corresponds to a sound-hard layer. We work with general geometry and arbitrary cloaked contents of the proposed cloaking device.

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BibTeX RIS

Hongyu Liu, Hongpeng Sun. 2011-10-04. Enhanced Near-cloak by FSH Lining. https://arxiv.org/abs/1110.0752

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